The two companies have labelled the tie-up a "strategic multi-year advertising, research and technology partnership" and said that they would work together to develop more effective advertising metrics and "attract non-traditional advertising partners".

Google's deal with NBC Universal marks a significant step in the company's ambition to become a one-stop shop for advertisers across all media by expanding its self-service AdWords system to other sectors.

"The Google TV ads platform is making television advertising more accountable and measurable and we are pleased with our progress to date," said Tim Armstrong, the president of advertising and commerce for Google North America.

"Our partnership with NBCU will help us to bring the power of television to a broader set of advertisers as well as give our current advertisers increased reach through our system," Armstrong added.

The two companies said the TV ad sales deal had the potential to be expanded to other NBC Universal properties.

As well as national TV ad sales the two companies have also agreed to work together to adapt Google's technology for use in local markets across the US.

"This is a great way to reach clients who are interested in buying television advertising but may not have previously had the resources or ability to do so," said Frank Comerford, the president of platform development and commercial operations at NBC Local Media.

NBCU said it would maintain its direct relationship with ad agencies, who fear being cut out of the ad sales market by Google, stating that it "can set parameters around the purchase of the available air time".

The two companies will share ad revenue and collaborate on a "series of custom marketing and research projects using the Google TV Ads platform".

Under Google's partnership with satellite pay-TV operator Dish Network, struck last year, its TV Ads platform can report second-by-second set top box data to improve advertiser feedback on ad viewing.

Google has existing agreements to sell adverts across dozens of US newspapers and bought dMarc, an automated network for selling radio ads.

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